What are the classifications of plastic bottle caps


The basic classification of plastic bottle caps: 1. Scr […]

The basic classification of plastic bottle caps:
1. Screwcap
As the name implies, a screw cap means that the cap is connected and matched with the container in a rotating way through its own screw structure. Benefiting from the advantages of the thread structure, when the screw cap is tightened, a relatively large axial force can be generated through the engagement between the threads, and the self-locking function can be easily realized.
2. Snap cover
The lid that fixes itself on the container through a structure such as a claw, we generally call it a snap lid. The snap cover is designed based on the high toughness of the plastic itself.
During installation, the jaws of the buckle cover can be deformed briefly when subjected to a certain pressure. Later, under the action of the elasticity of the material itself, the claws quickly return to their original shape and hug the mouth of the container, thereby fixing the lid on the container.
3. Welding cover
A type of cap that directly welds the mouth part of the bottle to the flexible package by means of welding ribs and other structures is called a welded cap. It is actually a derivative of the screw cap and the snap cap, but the liquid outlet of the container is separated separately and assembled on the lid.
The production process of plastic bottle caps:
Compression molding bottle cap production process
(1) The compression-molded bottle cap has no traces of the material opening and looks more beautiful. The processing temperature is low, the shrinkage is small, and the capsize is more accurate.
(2) Put the mixed material into the compression molding machine, heat the material to about 170 degrees Celsius in the machine to become a semi-plasticized state, and extrude the material into the mold quantitatively. The upper and lower molds are closed and pressed into the shape of a bottle cap in the mold.
(3) The compression-molded bottle cap remains in the upper mold, the lower mold is removed, the bottle cap passes through the rotating disk, and the bottle cap is removed from the mold in the counterclockwise direction of the internal thread.
(4) After the bottle cap is compressed and molded, it is rotated on the machine, and a knife is used to cut the anti-theft ring with multiple points connected to the bottle cap at 3 mm from the edge of the bottle cap.
Injection molding production process of injection bottle cap
(1) Put the mixed material into the injection molding machine, and heat the material to about 230 degrees Celsius in the machine to become a semi-plasticized state, and inject it into the mold cavity through pressure, and then cool and shape it.
(2) The cooling of the bottle cap shortens the counterclockwise rotation of the mold, and the bottle cap is pushed out under the effect of the push plate to complete the automatic fall of the cap. The use of threaded rotation demolding can ensure the complete forming of the entire thread.
(3) After cutting the anti-theft ring and installing the sealing ring in the bottle cap, a complete bottle cap is produced.
(4) After tightening the bottle cap, the bottle mouth is deepened from the top of the bottle cap to the sealing gasket, and the inner measuring groove of the bottle mouth and the thread of the bottle cap are in close contact with each other. Several sealing structures can effectively avoid the leakage or deterioration of the substance in the bottle.

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